Theatre Design & Technology - Winter 1978 - 9

tion of any point in a drawing can be mathematically determined in two operations: one to establish the distance above
or below a horizon line, the other to establish distance left or
right of a centerline (Figs. Sa, 5b).
you construct the perspective view on tracing paper. With
the system used here, the drawing can be constructed
directly on whatever surface you wish (illustration board,
watercolor paper, etc.)
2. Establish a Centerline and Proscenium (or Picture) Plane
on a floorplan of the setting. (Notice that the scale of the
f100rplan is irrelevant.) (Fig. 6.)
OPTION A: Superimpose a simple rectangular grid. This
simplifies the taking of measurements (Fig. 7).
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Figure 5a
Figure 6
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Figure 5b
The Steps in Constructing a Perspective View
by This System.
1. Tools and Materials Needed: Floorplan; elevation (or at
least knowledge of varying heights above stage/studio floor);
simple pocket calculator; engineer's scale (10, 20, 30, 40, 50,
60 divisions to the inch); and drawing materials.
NOTE: Your paper or illustration board need be no larger
than the finished drawing size you intend to have. This is a
big advantage over other systems in which you need a
distance point far off to one side, or the observer point
established in its real relationship to the floor plan (and
sometimes the observer point also laid out in relation to a
sectional elevation). Although the Perspective Grid system
does not call for a large paper surface, it does require that
USITT /Winter, 1978
Figure 7
OPTION B: It is possible to position the centerline and
picture plane (and grid) on an angle to the stage or setting,
for the sake of variety (Fig. 8). This results in a view of the
setting from a position to one side of the center of the
stage, auditorium or studio. (In Fig. 8, for example, the
observer would be somewhere left of house center along
an extension of the grid centerline.) If you decide to construct a view from a particular seat in the house or a particular camera position, start by establishing a centerline from
the observer position to the center of the setting. Then
create a picture plane line at right angles to that centerline
near the front of the setting. All measurements should be
made relative to these right-angled co-ordinate lines.
3. Establish the Observer Distance (how far from the stage/
proscenium plane a hypothetical observer will be). This might
relate to a particular seat in the house, a particular camera
position, etc.
Theatre Design & Technology
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